Update application style according to the system (WindowsXP, MacOS, X11)

Changelog

@@ -12,6 +12,7 @@
     - FEATURE: Added Autocompletion to search engine
     - FEATURE: Splitted BT & GUI parts (huge code rewriting & optimization)
     - FEATURE: New parameters for configure file to point to custom locations for libtorrent/libcurl
+    - FEATURE: Update application style according to the system (WindowsXP, MacOS, X11)
     - BUGFIX: Two torrents can now have the same name although they are different (use their hash)
     - BUGFIX: Fixed download from url that would fail sometimes
     - BUGFIX: Save directory was reset to default when filtering files in torrent

src/main.cpp

@@ -27,6 +27,14 @@
 #include <QTcpSocket>
 #include <QSettings>
 
+#ifdef Q_WS_WIN
+  #include <QWindowsXPStyle>
+#endif
+
+#ifdef Q_WS_MAC
+  #include <QMacStyle>
+#endif
+
 #include <stdlib.h>
 
 #include "GUI.h"
@@ -81,6 +89,12 @@ int main(int argc, char *argv[]){
     return 0;
   }
   QApplication app(argc, argv);
+#ifdef Q_WS_WIN
+  app.setStyle(new QWindowsXPStyle());
+#endif
+#ifdef Q_WS_MAC
+  app.setStyle(new QMacStyle());
+#endif
   QSplashScreen *splash = new QSplashScreen(QPixmap(":/Icons/splash.jpg"));
   splash->show();
   // Open options file to read locale